All ______ is needed is a supply of oil.
| A．the thing | B．that |
| C．what | D．which |
Many overseas Chinese look forward to________more about their roots in the summer camp．
| A．learn |
| B．be learning |
| C．learning |
| D．be learned |
—Where did you get these old doors?
—From the old houses which were________by the workers．
| A．taken down |
| B．pulled down |
| C．turned down |
| D．put down |
Things should________here before you enter the Great Museum．
| A．keeps |
| B．keep |
| C．be kept |
| D．are kept |
—There are only a few old city walls left．
—Yeah．Most of them________in the 1960s．
| A．pulled down |
| B．have pulled down |
| C．had pulled down |
| D．were pulled down |
—Mary，I have never seen a zoo that is________for animals to live in．
—Neither have I．
| A．possible |
| B．suitable |
| C．enjoyable |
| D．pleased |